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Pool Pilot "Check Flow"

I'm starting a new thread rather than bury my questions on the second page of a thread which may not pertain to me anyway.

My pool pilot is showing "check flow" and won't come on (of course). I've checked the flow -- cleaned the filter, all valves okay, and the flow itself (as shown by the in-ground cleaning and waterfall) is working fine. I checked the sensor -- clean as can be. It does show salt levels (so the chord is at least okay) and the connectors and cable looks fine.

I have an semi-opaque "flow valve"? (or whatever you call it) but I can't see if it's working because it's more opaque than it is semi. But when I remove all the stuff it appears that it is because I see water on the high or flow side of the loop but none on the other -- IOW, it's draining back but not forward (so if the valve was stuck open it would drain all the way). I suppose it could be opening up incorrectly but I don't know how to troubleshoot that. Besides what I don't understand is this (from the Pool Pilot site):

Check Valve - The check valve in the Manifold allows all water flowing through the plumbing at a rate greater than 20 gallons per minute to by-pass the production cell to maximize the production of chlorine.

Now -- this tells me that if the flow is TOO MUCH it will bypass the cell, not if the flow is too little. Is that right? Is it possible that somehow my flow is going too fast now? In any case, I really don't think it's a flow issue.

Do I just assume at this point I need a new tri-sensor? (Of course, if I replace that and it still doesn't work I'm pretty screwed and out $150).

Re: Pool Pilot "Check Flow"

Hi there, as we are still in our "slow" season, please be patient, it may take a bit longer than normal for someone experienced with this unit to assist you....good luck in a speedy resolution, wish I could help!

Re: Pool Pilot "Check Flow"

Thanks, I do understand -- I can't use my pool, but I also don't want it to turn green (seeing how the daytime temps are getting in the 80's here).

Tomorrow I'm going to put a lot of salt in just to make sure the salt part of the sensor is still working correctly (since it's a "tri" sensor I'm not quite sure what the third part does. Salt, flow and... temp? maybe). I'm also having a heck of a time even finding this part on the web -- the part they show doesn't look anything like mine.

In the meantime I'll just shock the pool and see if that keeps the chlorine high enough for now (water temp is still only around 50 or so so I think I'm okay for a while).

Re: Pool Pilot "Check Flow"

Pool Pilot uses a manifold that is supposed to regulate the flow rate going through the cell correctly for any total flow rate between 15 gpm and 100 gpm. If your flow rate was over 100 gpm, the cell would be getting too much water, not too little, which would present different symptoms.

The first place to look is the strainer inside the manifold. If you open up the unions on the Pool Pilot manifold, below the union on the side opposite the cell there is a strainer screen. If this screen becomes clogged you will have the exact symptom you describe.

After that, I would triple check the cable from the tri-sensor to the control box. Disconnect and check the connectors on both ends for bent pins and then reconnect them making sure you have a solid connection, also examine the entire length of the cable for cuts or nicks.

Another possibility, far far less likely, is that the semi-transparent spring valve at the bottom of the manifold has gotten stuck open. Normally it is transparent enough that you can see the spring move and watch for debris. This valve is really quite reliable, so this failure is quite unlikely.

The other part that can break is the flow sensor it's self, which is part of the tri-sensor assembly. If you are mechanically inclined you can open up the tri-sensor and test the flow switch yourself. Just be warned that this can get a little tricky, so it is usually best to rule out all of the other possibilities first.

Re: Pool Pilot "Check Flow"

Thanks, Jason, for the reply.

I have indeed already cleaned the screen (as well as cleaned out my filter and all other screens/skimmers). I'll check the cable again, but it seemed fine when I did remove the tri-sensor (I removed it to see if it needed cleaning). Also, since I'm getting salt and temp readings that would seem to indicate it's working at least for two of the sensors, right?

As I said, I can't see enough through the "semi-transparent" spring valve to see if it is opening and closing, but after removing the manifold the water on the far side of it does not drain backwards (as the water on the intake side does) telling me it must be closed properly.

I *assume* that having too low salt levels have nothing to do with this, right? Because the first symptom (before "Check flow") was telling me the salt was way too low. After reading here I assumed that maybe that did mean the cord was bad (since that was another sensor issue) but after I put a bit (one bag, which is all I had around here) of salt that complaint went away (although it still tells me I need to add salt when I go into diagnostics, it at least *reads* a salt level).

So that seems to leave the sensor itself. I've already opened it up once, and I do have a VOM and a tiny bit (not much) ability to check electrical things, so if it's possible for a lay person to check out the sensor I'd appreciate knowing how.

Re: Pool Pilot "Check Flow"

Yes, you can check the flow sensor, though it takes a little care. The tri-sensor assembly has a little paddle that sticks up into the water flow. When water is flowing it pushes on the paddle, the paddle has a magnet on it, when it gets close enough to the post it closes a switch magentically. There are various ways the paddle can be bent, broken, or stuck, preventing the switch from opening and closing as it should. There is a little more information in this post along with a wiring diagram in the attachment.

Re: Pool Pilot "Check Flow"

Okay, I'll check out that post.

Weird thing is, after the second time I opened up the tri-sensor and reassembled things and turned the pump back on this morning the system actually started and ran for a while (which is to say the autopilot turned on and all seemed well with no warning lights and seemingly doing its thing).

So I go back out after an hour and it's off again. I try boosting the level (right now it's around 30%, most likely due to how cold the water is) and then the "Add Salt" light comes on. It tells me to add 80lbs, and then stays off. I try increasing the level and then the "Check Flow" light comes on. But it doesn't stay on.

I'm going to add salt (I'm up to about 2400ppm now) but this all seems weird to me. I think I can rule out the cord now, since obviously things *are* getting communicated, I'm just not sure what is getting communicated. I was thinking that in putting the tri-sensor back together I somehow got the flow thing working again, but this on again/off again, add salt/check flow is beginning to drive me crazy.

Re: Pool Pilot "Check Flow"

The check flow condition will nearly always come on for a moment when the system first powers up the pump. If it blinks on for a moment while the pumps is running normally then it usually means you are right on the threshold of a low flow situation.

The salt level needs to be a little higher when the water is really cold than it needs to be in the summer. If your actual salt level is 2400, ie if the meter is working, and you are not heating the pool, then the salt level is rather low for winter usage.

There are some fairly rare situations that could cause actual low flow rates. Is the PSI reading on the filter about the same as it normally is? Both lower than usual filter pressure readings and higher than usual filter pressure readings can indicate a problem that causes low flow rates.

Re: Pool Pilot "Check Flow"

The PSI meter on my filter is the same as it always is, but I suspect that's because it doesn't work (I'm only guessing, but it's *never* changed in the four years I've had it even when the filter is very dirty).

The only way I can judge flow is the water cascading over the hot tub into the pool, and the fact the in-floor cleaning valves are opening and closing properly. A few days ago this was not the case -- there was a definite flow problem -- but after completely cleaning and recoating the filter the water is now flowing nicely back over the hot tub cascade and the in-floor valves are all working properly.

Right now the "Check Flow" message and light are not on -- they only come on now (since I opened up and checked the tri-sensor) when I try adjusting the percentage higher in order to turn the pilot on. It won't turn on (and it never goes above 32%). As soon as I stop pressing that up arrow the light goes off (although it then does warn me about low salt). So I'm going out now and getting some salt and seeing if perhaps the fact there's not enough salt is the real issue now (at least I'll get past that problem).

I'll report back here what happens after I add the 80lbs or so of salt it's asking for and perhaps you (or someone else) will have some more advice.

Re: Pool Pilot "Check Flow"

After putting 80lbs of salt (as requested by he Pilot) the unit appears fine, on and no more lights.

I *think* there was a flow problem initially, but the lights remained after i cleaned the filter. After removing the tri-sensor and taking the cord on and off and then putting the whole thing back together that seemed to have "fixed" it. Maybe that just shook the sensor enough to work, maybe the cable did have a problem that putting it on and off helped, maybe in fooling around with the clothes hanger and the manifold flow valve something cleared, but whatever the case I'm happy now.

(My next step would have been to try and check out the tri-sensor and I'll still do this if there are any repeat occurrences. Thanks for all the help.